The present invention relates to a multi-layered circuit substrate and a manufacturing method thereof, and more particularly, to a multi-layered circuit substrate and a method of preparing a multi-layered circuit substrate using a conductive ink and a metallic thin-film.
Mono-layered and multi-layered circuit substrates have been used widely for semiconductor packages. In response to the need for higher integration in semiconductor packages, the multi-layered circuit substrate is used since it can integrate many devices despite its small size. A conventional multi-layered circuit substrate is manufactured by depositing and etching each layer, resulting in a complicated manufacturing process. Furthermore, the material selected for the substrate is limited to a material capable of being etched.
To solve such problems, a method has been proposed by the present applicant whereby a circuit substrate is manufactured by printing a conductive ink on the substrate, instead of using an etching process. However, in the method of manufacturing the multi-layered circuit substrate, the conductive ink layer is prone to forming a round shape due to its viscosity. In addition, the conductive ink layer cannot ensure flatness due to the different sizes of ink particles, so that wire bonding on the conductive ink layer is difficult.